F J Whelan, L J Hall
The 16S rRNA gene has - and continues to - play an important role in microbiology. It's universality across prokaryotes and variation across species has allowed the sequencing of its hypervariable regions to be used to distinguish taxa within complex mixed bacterial communities. Although 16S rRNA gene sequencing has transformed our understanding of microbial communities, its use comes with important caveats and considerations, especially in light of the availability of whole-genome metagenomic sequencing. Within, we discuss the 16S rRNA gene and its important role in microbiome research, in the past, present, and future.